a) Technical Field of the Invention
The present invention relates to an improved structure of a Venetian blind, and in particular, to a Venetian blind of simple structure such that the cost of manufacturing is low, and the blind has an aesthetic appearance.
b) Description of the Prior Art
FIG. 1 shows a conventional Venetian blind having a substantially U-shaped head rail 10 formed by bending an iron plate or by plastic molding. The bottom of the head rail 10 is provided with a plurality of ladder cords 11 spaced apart forming a support for a plurality of slats 12. The bottom of the ladder cord 11 is provided with a heavy rod 13, and the top of the ladder cord 11 is mounted to a control device 20 to control a control rod 21 of the control device 20 so as to elevate the slats 12 at the sides of the ladder cord 11. Thus, the tilting angle of the slats 12 is adjusted to allow the amount of sunlight to enter. In addition, a plurality of vertical cords 14, passing through individual slats 12, are connected to the heavy rod 13 and one end thereof surrounds the head rail 10. Due to the positioning device 30 at one side of the head rail 10 extended to the bottom of the blind forming into a lift cord 15, the heavy rod 13 can be lifted up and the slats 12 are thus stacked one by one. By lowering the heavy rod 13, the individual slats 12 return to their spaced apart position.
However, there are drawbacks found in this conventional Venetian blind as follows:
1) There are various specifications for the Venetian blind, which are not easily adapted to window of various sizes. PA1 2) In order to comply with the size of the window, various types of head rails have to be made in order to insert the ladder cord 11, the vertical cord 14, the lift cord 15 and the control rod 20. Thus, the cost of manufacturing is increased. PA1 3) The strength of the conventional Venetian blind is insufficient as the head rail 10 is normally made from an iron plate and is bent into a "U" shaped structure. As there are a plurality of holes on the head rail 10, it cannot withstand heavy weight.